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Oxford University Press eBooks

Shadows of the Mind: A Search for the Missing Science of Consciousness

Roger Penrose

Published Jan 1, 1994• 1,061 citations
OpenAlex

Abstract

From the Publisher: A New York Times bestseller when it appeared in 1989, Roger Penrose's The Emperor's New Mind was universally hailed as a marvelous survey of modern physics as well as a brilliant reflection on the human mind, offering a new perspective on the scientific landscape and a visionary glimpse of the possible future of science. Now, in Shadows of the Mind, Penrose offers another exhilarating look at modern science as he mounts an even more powerful attack on artificial intelligence. But perhaps more important, in this volume he points the way to a new science, one that may eventually explain the physical basis of the human mind. Penrose contends that some aspects of the human mind lie beyond computation. This is not a religious argument (that the mind is other than physical) nor is it based on the brain's vast complexity (the weather is immensely complex, says Penrose, but it is still a computable thing, at least in theory). Instead, he provides powerful arguments to support his conclusion that there is in the conscious activity of the brain that transcends computation - and will find no explanation in terms of present-day science. To illuminate what he believes this something might be, and to suggest where a new physics must proceed so that we may understand it, Penrose cuts a wide swathe through modern science, providing penetrating looks at everything from Turing computability and Godel's incompleteness, via Schrodinger's Cat and the Elitzur-Vaidman bomb-testing problem, to detailed microbiology. Of particular interest is Penrose's extensive examination of quantum mechanics, which introduces some new ideas that differ markedly from those advanced in The Emperor's New Mind, especially concerning the mysterious interface where classical and quantum physics meet. But perhaps the most interesting wrinkle in Shadows of the Mind is Penrose's excursion into microbiology, where he examines cytoskeletons and microtubules, minute substructures lying dee

Related papers

Quantum mechanics and consciousness

F. Beck, Technische Hochschule Darmstadt

The first issue of JCS published an interview with Roger Penrose on his recent book Shadows of the Mind: A Search for the Missing Science of Consciousness (Clark, 1994). In it Professor Penrose, among other subjects, presented his views on the role of quantum mechanics on our way towards a better understanding of brain functioning and its relation to consciousness. In this note we comment on some aspects of his reasoning.

WORLD SCIENTIFIC eBooks•Oct 8, 2018•37 citations

Funda-mental Geometry: the Penrose-Hameroff ‘Orch OR’ Model of Consciousness

Stuart R. Hameroff

Abstract In The Emperor’s New Mind and Shadows of the Mind, Roger Penrose followed a delicate thread to begin to unravel the problem of consciousness. He concluded that conscious thought is more than computation—our minds utilize some type of non-algorithmic processing unavailable in computers. Regarding the identity of the proposed processing, the intrepid sleuth also searched for a ‘subtle and largely unknown physical principle’ capable of performing the needed non-computational actions. That principle was deduced to be ‘objective reduction’ (OR) of quantum coherent superposition, Penrose’s quantum gravity solution for the problem of wave function collapse in quantum mechanics. The next piece of the puzzle then became: where and how could quantum coherent superposition and OR occur in the brain? To that end, Penrose began collaboration with this author, who suggested that the logical and most likely source of macroscopic quantum effects in the brain lies in neuronal microtubules in the cell cytoskeleton.

•Apr 30, 1998•4 citations

Gödel, the Mind, and the Laws of Physics

Roger Penrose

Gödel appears to have believed strongly that the human mind cannot be explained in terms of any kind of computational physics, but he remained cautious in formulating this belief as a rigorous consequence of his incompleteness theorems. In this chapter, I discuss a modification of standard Gödel-type logical arguments, these appearing to strengthen Gödel's conclusions, and attempt to provide a persuasive case in support of his standpoint that the actions of the mind must transcend computation. It appears that Gödel did not consider the possibility that the laws of physics might themselves involve noncomputational procedures; accordingly, he found himself driven to the conclusion that mentality must lie beyond the actions of the physical brain. My own arguments, on the other hand, are from the scientific standpoint that the mind is a product of the brain's physical activity. Accordingly, there must be something in the physical actions of the world that itself transcends computation. We do not appear to find such noncomputational action in the known laws of physics, however, so we must seek it in currently undiscovered laws going beyond presently accepted physical theory. I argue that the only plausibly relevant gap in current understanding lies in a fundamental incompleteness in quantum theory, which reveals itself only with significant mass displacements between quantum states (“Schrödinger's cats”). I contend that the need for new physics enters when gravitational effects just begin to play a role. In a scheme developed jointly with Stuart Hameroff, this has direct relevance within neuronal microtubules, and I describe this (still speculative) scheme in the following.

Cambridge University Press eBooks•Jun 6, 2011•10 citations

Is Quantum Mechanics Relevant To Understanding Consciousness? A Review of Shadows of the Mind by Roger Penrose

Stanley A. Klein

1.1 The present essay explores three issues raised by Penrose in Shadows of the Mind (abbreviated Shadows from here on): (1) is classical (non-quantum) science incapable of understanding brain operation?; (2) are long-range quantum effects able to produce measurable changes in neural activity?; (3) why have so many researchers proposed a strong connection

PSYCHE: An Interdisciplinary Journal of Research On Consciousness•Jan 1, 1995•5 citations

Mind at Light Speed: A New Kind of Intelligence

David D. Nolte

In this fascinating book David Nolte explains the technology behind the bandwidth revolution and reveals the future of artificial intelligence. From a leading computer scientist and physicist comes proof that the days of computing with clunky electrons (particles of matter) are just about over, and that the use of photons (particles of light) will change the nature of computing and intelligence, artificial or otherwise, forever. Next generation computers won't just read, they will see, and they will do so faster than we can imagine. Exploring the startling possibilities this would allow, Nolte explains the Intelligent Internet (the net won't just be a database, it will make decisions); light computers (how fibre optics, which speed up the flow of information between computers, will speed up the flow inside them); and hologram hard drives (capable of accessing everything at once). Roger Penrose's The Emperor's New Mind argued that we couldn't understand human consciousness because of the difficulty of engineering - and understanding - at the quantum level. A truly revolutionary work, Machines of Light showed that not only is quantum light technology possible but that its applications will take our understanding of what intelligence actually is to the next level. But the implications of the technology described in this book are more than philosophical. The implications of this revolution for business in our new economy and for satisfaction in our daily lives are simply staggering.

•Jan 1, 2001•18 citations

Essay on mesoscopic and quantum brain

Haret Codratian Rosu

In the pure essay style (no mathematical formulas), I present a number of speculative reflections and suggestions on possible applications of mesoscopic methods and of quantum mechanical concepts to as such a complex system as the human brain. As an initial guide for this essay I used ``The Emperor's New Mind" of Roger Penrose

arXiv:gr-qc/9409007•Sep 5, 1994•6 citations
From the Publisher:
A New York Times bestseller when it appeared in 1989, Roger Penrose's The Emperor's New Mind was universally hailed as a marvelous survey of modern physics as well as a brilliant reflection on the human mind, offering a new perspective on the scientific landscape and a visionary glimpse of the possible future of science. Now, in Shadows of the Mind, Penrose offers another exhilarating look at modern science as he mounts an even more powerful attack on artificial intelligence. But perhaps more important, in this volume he points the way to a new science, one that may eventually explain the physical basis of the human mind. Penrose contends that some aspects of the human mind lie beyond computation. This is not a religious argument (that the mind is other than physical) nor is it based on the brain's vast complexity (the weather is immensely complex, says Penrose, but it is still a computable thing, at least in theory). Instead, he provides powerful arguments to support his conclusion that there is in the conscious activity of the brain that transcends computation - and will find no explanation in terms of present-day science. To illuminate what he believes this something might be, and to suggest where a new physics must proceed so that we may understand it, Penrose cuts a wide swathe through modern science, providing penetrating looks at everything from Turing computability and Godel's incompleteness, via Schrodinger's Cat and the Elitzur-Vaidman bomb-testing problem, to detailed microbiology. Of particular interest is Penrose's extensive examination of quantum mechanics, which introduces some new ideas that differ markedly from those advanced in The Emperor's New Mind, especially concerning the mysterious interface where classical and quantum physics meet. But perhaps the most interesting wrinkle in Shadows of the Mind is Penrose's excursion into microbiology, where he examines cytoskeletons and microtubules, minute substructures lying dee
Abstract In The Emperor’s New Mind and Shadows of the Mind, Roger Penrose followed a delicate thread to begin to unravel the problem of consciousness. He concluded that conscious thought is more than computation—our minds utilize some type of non-algorithmic processing unavailable in computers. Regarding the identity of the proposed processing, the intrepid sleuth also searched for a ‘subtle and largely unknown physical principle’ capable of performing the needed non-computational actions. That principle was deduced to be ‘objective reduction’ (OR) of quantum coherent superposition, Penrose’s quantum gravity solution for the problem of wave function collapse in quantum mechanics. The next piece of the puzzle then became: where and how could quantum coherent superposition and OR occur in the brain? To that end, Penrose began collaboration with this author, who suggested that the logical and most likely source of macroscopic quantum effects in the brain lies in neuronal microtubules in the cell cytoskeleton.
Gödel appears to have believed strongly that the human mind cannot be explained in terms of any kind of computational physics, but he remained cautious in formulating this belief as a rigorous consequence of his incompleteness theorems. In this chapter, I discuss a modification of standard Gödel-type logical arguments, these appearing to strengthen Gödel's conclusions, and attempt to provide a persuasive case in support of his standpoint that the actions of the mind must transcend computation. It appears that Gödel did not consider the possibility that the laws of physics might themselves involve noncomputational procedures; accordingly, he found himself driven to the conclusion that mentality must lie beyond the actions of the physical brain. My own arguments, on the other hand, are from the scientific standpoint that the mind is a product of the brain's physical activity. Accordingly, there must be something in the physical actions of the world that itself transcends computation. We do not appear to find such noncomputational action in the known laws of physics, however, so we must seek it in currently undiscovered laws going beyond presently accepted physical theory. I argue that the only plausibly relevant gap in current understanding lies in a fundamental incompleteness in quantum theory, which reveals itself only with significant mass displacements between quantum states (“Schrödinger's cats”). I contend that the need for new physics enters when gravitational effects just begin to play a role. In a scheme developed jointly with Stuart Hameroff, this has direct relevance within neuronal microtubules, and I describe this (still speculative) scheme in the following.
In this fascinating book David Nolte explains the technology behind the bandwidth revolution and reveals the future of artificial intelligence. From a leading computer scientist and physicist comes proof that the days of computing with clunky electrons (particles of matter) are just about over, and that the use of photons (particles of light) will change the nature of computing and intelligence, artificial or otherwise, forever. Next generation computers won't just read, they will see, and they will do so faster than we can imagine. Exploring the startling possibilities this would allow, Nolte explains the Intelligent Internet (the net won't just be a database, it will make decisions); light computers (how fibre optics, which speed up the flow of information between computers, will speed up the flow inside them); and hologram hard drives (capable of accessing everything at once). Roger Penrose's The Emperor's New Mind argued that we couldn't understand human consciousness because of the difficulty of engineering - and understanding - at the quantum level. A truly revolutionary work, Machines of Light showed that not only is quantum light technology possible but that its applications will take our understanding of what intelligence actually is to the next level. But the implications of the technology described in this book are more than philosophical. The implications of this revolution for business in our new economy and for satisfaction in our daily lives are simply staggering.